Mapping the Grid

I navigated the perimeter of the mahogany desk toward a low pool of light. Spread beneath an inkwell lay an unfolded transit map, its grid lines charting the dark streets beyond the glass. I knelt beside the central crease, extending a gauntlet to trace the arterial routes branching outward. Next to my boot rested a brass drafting compass. Turning its knurled wheel, I aligned its steel needle with the junction corresponding to this sector. The city beyond the pane is extensive, but it is governed by geometry. I have charted its perimeter.